How to output things in the statusBar bar

Hello everyone, I want to control the status bar or warning pop-up window and output some things. How should I do it? Who can guide me? Thank you

I tried to output this way, but he reported an error to me. I don't know what to do. I may not know much about pyqt before

Depends what it's called in designer, but roughly this for the status bar:

self.w.statusbar.showMessage(message, timeout * 1000)

STATUS.emit('error', linuxcnc.OPERATOR_ERROR, 'message')

in master also:
ACTION.SET_DISPLAY_MESSAGE('MESSAGE')
ACTION.SET_ERROR_MESSAGE('MESSAGE')

I didn't add a status bar in my designer, and I don't know its name, but when I started it, the status bar existed. I don't know how to use the status bar, because I also want to output something in the status bar. I hope you can help me solve it. Thank you for your help

it you start with a mainWindow, statusbar is added automatically and is called stausbar

try:

self.w.statusbar.showMessage('My message', 8000)

OK, thank you very much. I tried your method. Now I can output something on the status bar.
Thank you again